1. Technical Field
The present invention relates to a screen and a projection system.
2. Related Art
In the past, there have been used various types of screens as projection surfaces for enlarged images used for image viewing with projectors (projecting display devices) in, for example, presentations in exhibitions, academic conferences, meetings, and so on, and home theaters.
In related art screens there exists a problem that the contrast as a luminance ratio between “white (the maximum luminance)” and “black (the minimum luminance)” is low in bright places, and it is difficult to display clear images because, in the case of reflective screens, for example, the screens reflect the light projected from projectors to thereby display the projection images, and at the same time, also reflect outside light derived from use environments such as illumination light or sunlight. Therefore, development of a screen aimed to realize an improved contrast in bright rooms by suppressing the influence of the outside light causing the degradation in the contrast such as sunlight or illumination light to thereby lower the minimum luminance is in progress.
As such a screen there is proposed one having a configuration in which a light absorption layer including dye or a pigment absorbing light is provided to thereby absorb unwanted outside light (see, e.g., JP-A-2002-107828).
In the configuration described in the document mentioned above, there is formed a layer structure composed of a scattering layer and a light absorbing layer stacked in this order from the light entrance side. However, in such a configuration, since the wavelength component of the light on which the outer light absorption process is not performed is reflected toward the viewing side (the side of the observer) due to the backscattering on the surface of the scattering layer, the effectiveness of improvement in contrast by the light absorbing layer is not sufficient, and the chromatic purity is degraded. Further, the scattering material included in the scattering layer is often high in cost, and moreover, the process required for providing the scattering layer increases the number of processes, which also causes increase in cost of manufacturing a screen.